The present invention relates to a manufacturing method for a sensor component and a sensor component, in particular a thin-film high-pressure sensor that has a substrate, on which at least one functional film that is to be provided with contacts is to be applied. High-pressure sensors of this type are used in numerous systems in the motor vehicle, for example, in direct gasoline injection. High-pressure sensors are also used in the field of automation technology. The function of these sensors is based on the conversion of the mechanical deformation of a membrane, which is brought about by the pressure, into an electric signal using a thin-film system. German Patent No. 100 14 984 describes thin-film systems of this type, having high-pressure sensors. They have a silicon dioxide film for the electric insulation of the functional film from the high-grade steel substrate. However, known manufacturing systems for semi-conductor methods are not prepared for the processing of high-grade steel substrates that are 5 millimeters thick and up to 850 grams in weight, for example.
The method according to the present invention and the sensor component according to the present invention have, in contrast, the advantage that an electric insulation of the measuring elements is ensured by the membrane, without having to apply insulating films, such as silicon dioxide films for example, separately onto the membrane. In this way, the processing can be performed using standard systems, since a material with a thickness of less than one millimeter, which is compatible with manufacturing systems that are currently available for semiconductor methods, can be used as an electrically insulating substrate. Thus, it is no longer necessary to adapt the production equipment for the application of the thin films to the use of high-grade steel membranes, for example. Furthermore, costs for the production equipment, which is necessary for the application of a silicon dioxide film that is several micrometers thick, can be avoided. Insulating substrates that are self-supporting are, in addition, easy to handle in the context of the application of the resistor, contact, and passivation films.
It is especially advantageous to use thin glass as an electrically insulating substrate, which ensures a good electric insulation in a cost-effective manner, is stable and thus easy to handle, and furthermore, can be attached to a membrane using anodic bonding. Other attachment methods such as, for example, adhesion, are also possible.